1. Field of the Invention
The present invention relates to a leading-edge flap system which achieves optimization of a schedule for control of a leading-edge flap in general aircraft.
2. Description of the Prior Art
The schedule for control of a leading-edge flap angle in the prior art was determined through an extensive wind tunnel test by making use of an angle of attack (.alpha.) and a Mach number (M) as parameters. As shown generally in FIG. 6, the schedule for control was preset in a central computer 02, and an angle of a leading-edge flap 01 was controlled by the flight conditions (.alpha., M) via a drive unit 03 and an actuator 04. Since a leading-edge flap 01 is normally formed as a single unit (and thus has the same flap angle) over the entire wing span, and because of the method of determination of the schedule as described above, it is not always guaranteed that optimization with respect to performance and loading is established.
More particularly, the above-described leading-edge flap system in the prior art involved the following problems to be resolved:
(1) Due to influence of the Reynolds number effect or the like which occurs in wind tunnel-testing, optimum results obtained in the wind tunnel tests will generally not correspond to optimum conditions in actual aircraft with respect to performance and loading. PA0 (2) In the event that the schedule determined through wind tunnel testing has been found less than optimum, rectification of the schedule through a flight test is expensive and time-consuming. PA0 (3) In a conventional airframe, the leading-edge flap is formed as a single unit along the direction of the wing span, and accordingly, in some cases, variation of airflow along the direction of the wing span cannot be accommodated in a suitable manner because the flap angle is constant along the wing span. PA0 (4) In relation to items (1) and (2) above, extensive wind tunnel testing is necessary, thus resulting in considerable time consumption and expense.